Perhaps you should try some spelling variations:
chieu xanh » chieu sach, chieu tinh, hieu manh
chieu sang » chieu sach, hieu lang, nhieu tang
hanh trung » thanh trung, hanh trang, manh trung
cong tan » cong tac, cong san, cong thanh
tan toan » tan tran, tap toan, van toan
toan cau » toan cao, toan ban, toan tap
co dang » cao dang, co dong, xo dang
co dan » co ban, ca dan, cao dang

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu xanh) OR (chieu sang)) - hanh trung ((co dang) OR (co dan)) cong tan toan cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chieu xanh) or (chieu sang)) - hanh trung ((co dang) OR (co dan)) cong tan toan cau~".
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu xanh) or (chieu sang)) - hanh trung ((co dang) OR (co dan)) cong tan toan cau*.